The Israeli ambassador to Britain, Zvi Heifetz, has accused the National Union of Journalists of "petty, one-sided politics" after a call for its members to boycott goods from his country.

Mr Heifetz's comments came as the NUJ issued a statement that urged its members to report Israeli-Palestinian stories fairly, after delegates at its annual conference on Friday voted to call for a boycott of Israeli goods as a protest against last year's war in Lebanon.

"It is a shame that an organisation which represents journalists and the principles of balance and impartiality, should threaten to boycott goods from Israel," Mr Heifetz said.

"The timing of this move is also peculiar, coming just days after worrying rumours surfaced about the fate of one of the union's own members and at a time when Israeli and Arab leaders are looking for ways to revive the peace process," he added.

"The recent bi-weekly meetings between [Israeli prime minister] Olmert and [Palestinian] president Abbas, and the attempts made by the Arab world and Israel to explore the possibilities created by the Saudi initiative, offer quite a contrast to the NUJ's petty, one-sided politics."

Mr Heifetz spoke as the NUJ released a statement stressing that members should maintain the normal principles of free reporting on Palestinian and Israeli issues.

"The boycott call has nothing to do with reporting," said the statement from the union, which has more than 39,000 members.

"The NUJ is not telling members how to report Israel - beyond its permanent injunctions to members to report independently and fairly on all matters, and not to produce racist or discriminatory copy.

"The union has not and never would adopt a line on how any issue should be reported. We stand for free reporting and free speech - and we criticise those, including the Palestinian and Israeli authorities, when they act against journalists' freedom to report."

The union statement also linked the Israeli boycott call to the kidnapping of BBC Gaza correspondent Alan Johnston.

"The call for the boycott in part related it to the kidnap of Alan Johnston. The Palestinian journalists union has given huge support to the campaign for his release - holding demonstrations and strikes against the Palestinian authority to demand more action from them," the NUJ said.

"The decision made by elected representatives at our conference was a decision of NUJ members as trade unionists and as citizens to try to help put pressure on the Israeli government to reverse its block of these payments, its refusal to recognise Palestinian journalists carrying the international press card and the general damage being done by the continued occupation."

The NUJ statement told members that they could seek to revoke the Israeli boycott motion, which was passed at the union's annual delegate meeting in Birmingham by 66 votes to 54.

Friday's motion to boycott Israeli goods was part of a series on international affairs.

The vote on the motion was taken after it was split from a larger motion that condemned the "savage, pre-planned attack on Lebanon by Israel" last year and called for the end of Israeli aggression in Gaza and other occupied territories.

But the motion calling for the boycott of Israeli goods has received the lion's share of attention - to the anger of some union officials who believe it deflects attention away from the union's campaigning on industrial issues.

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